Backport PR #48490 on branch 1.5.x (CI: Use -j1 for python-dev build to avoid flaky build error) (#48517)

Backport PR #48490: CI: Use -j1 for python-dev build to avoid flaky build error

Co-authored-by: Matthew Roeschke <[email protected]>

Author: meeseeksmachine

.github/workflows/python-dev.yml

@@ -80,9 +80,10 @@ jobs:
         python -m pip install python-dateutil pytz cython hypothesis==6.52.1 pytest>=6.2.5 pytest-xdist pytest-cov pytest-asyncio>=0.17
         python -m pip list
 
+    # GH 47305: Parallel build can cause flaky ImportError from pandas/_libs/tslibs
     - name: Build Pandas
       run: |
-        python setup.py build_ext -q -j2
+        python setup.py build_ext -q -j1
         python -m pip install -e . --no-build-isolation --no-use-pep517
 
     - name: Build Version